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Development of an ultra-safe, ultra-low emissions natural gas fueled school bus: Final report

Technical Report ·
DOI:https://doi.org/10.2172/650250· OSTI ID:650250
 [1]
  1. Southwest Research Inst., San Antonio, TX (United States)
This report documents work conducted under Southwest Research Institute (SwRI) Project 03-6871, ``Development of an Ultra-Safe and Low-Emission Dedicated Alternative Fuel School Bus.`` The project was sponsored by the National Renewable Energy Laboratory (NREL) under Subcontract No. ZCF-5-13519-01. This report documents Phase 3 -- Integration and Phase 4 -- Demonstration and serves as the final report for this project. Phase 1 -- Systems Design and Phase 2 -- Prototype Hardware Development were documented in NREL publications TP-425-7609 and TP-425-2 1081, respectively. Several significant areas of work are summarized in this report. Integration of the engine technologies developed under Phase 2 into a production Deere 8.1-L, spark-ignition compressed natural gas engine is detailed, including information on the engine and control system modifications that were made. Federal Test Procedure (FTP) emissions results verifying the ultra-low emissions output of this engine are also included. The informal project goal of producing oxides of nitrogen (NO{sub x}) emissions less than or equal to 1.0 g/bhp-hr over the FTP heavy-duty engine cycle was attained. In addition, a test run that resulted in less than one half of the Ultra-Low Emissions Vehicle limit for NO{sub x} plus non-methane hydrocarbons was obtained. These results were for engine-out (no catalyst) emissions. Results using a catalyst produced very low formaldehyde emissions and virtually zero carbon monoxide and particulate matter emissions. Following these excellent results, a duplicate engine was assembled and integrated into the prototype ultra-safe school bus, the Envirobus 2000. Many of the new and modified subsystems developed during this project for the engine are considered strong candidates for inclusion into the production Deere 8.1-L gas engine in the near future.
Research Organization:
National Renewable Energy Lab., Golden, CO (United States); Southwest Research Inst., San Antonio, TX (United States)
Sponsoring Organization:
USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)
DOE Contract Number:
AC36-83CH10093
OSTI ID:
650250
Report Number(s):
NREL/SR--540-23842; ON: DE98004262
Country of Publication:
United States
Language:
English